# Relationship history for MSHA mine 4202752

Current hierarchy: **Alec  Green → M.C. Green & Sons, Inc. → Portable Crusher 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** M.C. Green & Sons, Inc. → Portable Crusher 1; 2023-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Alec  Green → Portable Crusher 1; 2023-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alec  Green → M.C. Green & Sons, Inc.; 2023-07-20 to current/open; source msha-controller-operator-history